(CNN) — When Jonathan the giant tortoise was born, Queen Victoria was just a teenager.
While the British monarch died more than 120 years ago aged 81, Jonathan is still shuffling around planet Earth.
Perhaps the most famous resident of St. Helena, one of the world's remotest islands, Jonathan is this year celebrating his 190th birthday -- making him the oldest tortoise ever to live.
According to Guinness World Records, Jonathan is the oldest-ever chelonian -- a category that encompasses all turtles, terrapins and tortoises.
Thought to have been born around 1832, Jonathan was gifted to Sir William Grey-Wilson -- who later became governor -- arriving in St. Helena from the Seychelles in 1882. A further 31 governors have come and gone in the decades since.
In truth, Jonathan could even be 200 years old as nobody knows his exact age, according to Matt Joshua, head of tourism on St. Helena.
He told CNN: "Jonathan could actually be 200 because the information regarding his arrival on the island is not exact and because there's no real record of his birth."
This picture was taken soon after Jonathan arrived on the island, by which time he was at least 50.
Further proof of his age emerged when an old photograph taken between 1882 and 1886 was uncovered. In it, a fully grown Jonathan can be seen grazing in the garden of Plantation House, the residence of the Governor of St. Helena, where he has spent most of his life.
The previous oldest chelonian was Tu'i Malila, a radiated tortoise that lived to be at least 188. Presented to the royal family of Tonga by British explorer Captain James Cook in around 1777, Tu'i Malila died in 1965.
The world may have changed immeasurably, but Jonathan's life still consists of eating, sleeping and mating.
Since Jonathan was born, the world has changed immeasurably -- the first photograph of a person was taken in 1838, the incandescent lightbulb was invented in 1878, the first power-driven flight took to the skies in 1903, and in 1969 Neil Armstrong and Buzz Aldrin became the first people on the Moon. Not to mention two world wars and the arrival of the internet.
Nevertheless, Jonathan's world has changed little in almost two centuries -- his main interests remain sleeping, eating and mating.
He is fed by hand as old age has left him blind and with no sense of smell and so is unaware of food if it is simply placed on the ground.
His hearing, however, is excellent, and he responds well to the sound of his vet's voice, according to Guinness World Records.
His vet, Joe Hollins, told the GWR that despite some of his senses now failing, Jonathan still has plenty of energy -- though this varies with the weather.
"On mild days, he will sunbathe -- his long neck and legs stretched fully out of his shell to absorb heat and transfer it to his core," he said.
In colder weather, he prefers to "dig himself into leaf mold or grass clippings and remain there all day."
Jonathan has seen governors and royalty come and go in his long lifetime. Here he is with the Queen and her family as a young woman.
Living alongside three other giant tortoises -- David, Emma and Fred -- Jonathan's favorite foods include cabbage, cucumber, carrot, apple and other seasonal fruits.
Hollins added: "In spite of his age, Jonathan still has a good libido and is seen frequently to mate with Emma and sometimes Fred -- animals are often not particularly gender-sensitive!"
The elderly animal is something of a celebrity on the island, located in the South Atlantic.
Joshua said: "There are generations and generations of St. Helenians, aka Saints, who have pictures of granny with him as a child.
"He's really well loved and people look out for him."
Officials on the island are currently working on Jonathan's birthday celebrations, which are planned for later this year. A series of commemorative stamps will be issued and anyone who visits him this year will receive a certificate featuring the first known picture of his footprint.
Top image credit: Mathias Falcone